Conventionally, the synthetic resin pattern sheet used for the shower curtain or the like, as well-known, forms at a synthetic resin sheet uneven colored patterns.
The synthetic resin pattern sheet is colored by the well-known valley dying printing method in such a manner that an embossing roll having the uneveness at the surface corresponding to the patterns is used, printing ink is applied to the projections at the embossing roll surface, a synthetic resin sheet is applied in a press-contacting manner to the embossing roll so as to form the patterns on the synthetic resin sheet, and sumultaneously the patterns are colored with the printing ink.
As another coloring method, a silk-screen printing method has been well-known which, after the embossing roll is used to form patterns on the synthetic resin sheet, carries out silk-screen printing in synchronism with the patterns, thereby coloring the patterns.
The synthetic resin pattern sheet obtained by the above coloring methods is colored only at the patterns on the synthetic resin sheet with the printing ink and distinct at the border between the colored pattern and the not-colored portion, thereby enabling the colored patterns to be displayed with emphasis to the exterior.
The synthetic resin pattern sheet, as the above-mentioned, distinguishes the colored patterns from the not-colored portions so as to demonstrate the stereo effect by polychrome printing, but the patterns are merely all over colored with the printing ink. Therefore, in a case where, for example, patterns of leaves and flowers of plants are formed, the natural color tone or lightness of plants is not variable in a continuing manner, so that variation in depth of each pattern cannot appear, thereby creating the problem in that the patterns on the synthetic resin sheet are less in the natural feeling and stereo effect.